September weather forecast
Saint John, VI

Despite heading towards the tail end of summer, September in Saint John brings no reprieve from the warmth. The tropical maritime climate is at its zenith during this period, with plenty of sun-soaked days to enjoy. The high point featuring September weather is the substantial increase in rainfall, registering a notable 5.6" (142mm). Locals and visitors can expect an interplay of hot sunny days and refreshing evening showers.

Temperature

Saint John sees the highest average temperatures during the months of August and September, peaking at 87.8°F (31°C).

Rainfall

In Saint John, during September, the rain falls for 16 days and regularly aggregates up to 5.63" (143mm) of precipitation. Throughout the year, there are 156 rainfall days, and 49.69" (1262mm) of precipitation is accumulated.

Ocean temperature

September and October, with an average ocean temperature of 84.2°F (29°C), are months with the warmest seawater.
Note: For engaging in any water activities, temperatures from 77°F (25°C) to 84.2°F (29°C) are viewed as outstanding and exceptionally pleasing for prolonged durations.

Daylight

The average length of the day in September is 12h and 14min.
On the first day of the month, sunrise is at 6:04 am and sunset at 6:32 pm. On the last day of September, sunrise is at 6:09 am and sunset at 6:08 pm AST.

Sunshine

In Saint John, the average sunshine in September is 8h.

UV index

The months with the highest UV index are March through September, with an average maximum UV index of 12. A UV Index estimate of 11, and higher, represents an extreme health hazard from exposure to the Sun's UV radiation for average individuals.
Note: The daily maximum UV index of 12 in September interprets into the following advice:
Employ every precaution of importance, unprotected skin and eyes could burn within moments. UV radiation from the Sun is most intense between 10 a.m. and 4 p.m. Try to avoid direct sunlight during this period. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days. Even if the day is cloudy, sunscreen with SPF of at least 30 should be applied generously and reapplied often, particularly after swimming or outdoor exercise. Attention! The reflection of both water and sand can increase the intensity of UV rays.